BlackRock is the world’s largest asset manager and its iconic iShares brand of exchange-traded funds continues to see money pour in. BlackRock (BLK) on Monday disclosed a slew of changes it made in its overall stock holdings as of Dec. 31, including buying more shares of Chipotle Mexican Grill (CMG), Berkshire Hathaway (BRKB) class B and Applied Materials (AMAT).